It is well known to provide a closure and container combination with some variation of tamper-evident, or tamper-indicating assembly. The closures normally incorporate a cap portion connected to a band portion. Such a closure may be seen in the prior art FIG. 2, where the cap portion 1 is integrally connected to the tamper-evident band portion 2. Upon affixation of the closure onto a neck of a container, a set of n tabs, 3a to 3n, generally denoted as 3k and connected to the bottom of the band portion, which have elements directed inwardly and upwardly, engage an annular bead on the container neck. Upon the unthreading, and thus removal, of the cap portion, the band is separated from the cap and is retained on the container's neck. This is accomplished by the unthreading of the cap giving rise to an overall upward movement of the cap. Because of the action of the tabs against the annular bead, the tamper-evident band is prevented from moving upward. As a result, the band is separated from the cap as the latter moves upward with the unthreading motion. After the band is fully separated from the cap, it remains with the container neck and provides the user with evidence that the container and its contents may have been tampered with.
It is known that there are various container designs employed to assist in the operation of band portions from cap portions upon removal of the cap from the container. These designs typically use various locking assemblies whereby the band portion engages notches, or the like below the threading on the neck container to break the connectors and thereby separate the band portion when the cap is attempted to be removed.
The current tamper-evident closure designs sufficiently accomplish their intended purpose, that is, to provide the user with evidence of container tampering. Yet, for the average customers, the tamper-evident closure has become more of an obstacle than a useful benefit. In some cases the tamper-evident closure assembly is difficult, if not impossible, to remove by twisting the cap portion with the human hand. Unable to break the connectors and remove the cap by hand, users sometime incorporate sharp tools or kitchen utensils to break the band from the cap.
The problems associated with presently available tamper-evident closures is particularly acute when the user is a child, elderly person, or is simply physically unable to unthread the closure assembly. Cap designs such as that shown in U.S. Pat. No. 5,137,163 to Moore and U.S. Pat. No. 4,458,821 to Ostrowsky possess the ability to facilitate removal of the cap portion from the neck portion by using an angled annular bead to break the tabs of the cap band portion. However, such closures with angled annular bands may tend to apply undesirable stresses to the closure during the unthreading process. In particular, when the tamper-evident band is almost completely stripped off, the cap is at the furthest vertical distance from the annular bead. The significant distortion of the tamper-evident band may cause a corresponding distortion of the cap, and the band may actually not separate from the closure. If the closure is child-resistant, and thus requires additional manipulation, the difficulty in opening may be significantly increased.
Another problem associated with tamper-evident closure designs that utilize an annular bottle bead to engage tabs on a TE cap is the ability of some caps to be partially removed, breaking the cap/bottle seal, but not unthreaded enough to cause noticeable TE band distortion/separation.
There is a need for a tamper-evident container in which the benefits of a ramped annular bead, namely ease of closure removal, are obtained without the corresponding distortion. There is further a need for a tamper-evident container/closure system that accelerates closure/band separation and for containers in which a number of current tamper-evident closures may be accommodated.